JP4286065B2 - Vane pump - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vane pump, and more particularly to an improved technique of a vane pump used in a CVT or the like that is a continuously variable transmission for an automobile.
[0002]
[Prior art]
The rotor in the vane pump has a structure in which both side surfaces are sandwiched and covered by a pair of side plates, and a vane guide is provided only on one side plate of the pair of side plates, and the other side plate. There is no vane guide. For this reason, on the side plate side where the vane guide is not provided, the side surface of the rotor and the side plate face each other without interposing the vane guide. On the other hand, on the side plate side where the vane guide is provided, an annular groove for the vane guide is formed on the side surface of the rotor (see, for example, Patent Document 1).
[0003]
[Patent Document 1]
A microfilm (pages 5-7, FIGS. 3-5) of Japanese Patent Application No. 57-1559587 (Japanese Utility Model Publication No. 59-64485)
[0004]
[Problems to be solved by the invention]
As shown in FIGS. 10 to 12, the vane pump described in Patent Document 1 described above includes a rotor 020 fixed to a drive shaft 05 coupled to a drive unit of an internal combustion engine, and an outer peripheral portion of the rotor 020. A vane 021 that is slidable along the inner peripheral cam surface 012a of the cam ring 010 that is movable forward and backward in the radial direction and that is disposed outside the outer peripheral portion of the rotor 020, and both side surfaces of the rotor 020 and the cam ring 010 are A pair of side plates (cover plates, side plates) 030 and 040 are provided so as to be sandwiched therebetween.
[0005]
One side plate (cover plate) 030 of the pair of side plates 030, 040 is provided with a vane guide 032 for guiding the vane 021. The vane guide 032 is the one side plate. It protrudes from the surface of 030, and its outer shape is similar to the inner peripheral cam surface 012a of the cam ring 010. On the other hand, the other side plate (side plate) 040 is not provided with such a vane guide.
[0006]
An annular groove 023 for receiving the vane guide 032 is formed on one side surface of the rotor 020 facing one side plate (cover plate) 030 provided with the vane guide 032. The annular groove as described above is not formed on the other side surface of the rotor 020 that faces the other side plate (side plate) 040 that is not provided, and the other side surface has a large area in the side plate 040 in that sense. Facing in the face-to-face area.
[0007]
By the way, as described above, of the both side surfaces of the rotor, the one side surface faces the side plate provided with the vane guide, but the other side surface faces the side plate not provided with the vane guide. Accordingly, the other side surface of the rotor facing the side plate not provided with the vane guide faces the side plate without interposing the vane guide or the annular groove for the vane guide. Therefore, it is conceivable that the side plate is in direct and strong contact with the side surface of the rotor. Further, since the facing surface area is large, sometimes the oil film is cut and seizure occurs due to generation of frictional heat due to the sliding contact.
[0008]
Therefore, in order to solve the above problems, it is proposed that side plates provided with vane guides on both sides of the rotor face each other. However, the side plates provided with vane guides on both sides of the rotor are proposed. Arranging the plates leads to an increase in size of the pump unit.
[0009]
In addition, annular grooves for vane guide accommodation must be formed on both side surfaces of the rotor, and the formation of such annular grooves increases the number of groove formation portions in the rotor structure. This increase directly weakens the rotor structure and reduces the strength of the rotor itself. In order to maintain the proper strength of the rotor, it is necessary to increase the thickness of the rotor itself, and the rotor becomes larger by that amount, leading to an increase in the size of the pump.
[0010]
In the situation as described above, the vane guide is interposed only on one side of the rotor without arranging the side plate provided with the vane guide on both sides of the rotor. Assuming a rotor structure in which an annular groove is provided only on one side surface of the rotor, sliding between the side surface and the side plate on the other side surface of the rotor facing the side plate not provided with the vane guide There is a need to develop an improved vane pump structure that can effectively prevent seizure by contact.
[0011]
[Means for solving the problems and effects]
  The present invention relates to an improved structure of a vane pump for solving the above-mentioned problems, and in particular, an improvement for preventing seizure due to sliding contact with a side plate on a side surface of a rotor facing a side plate not provided with a vane guide. Regarding the structure, a cam ring having a cam surface on an inner peripheral surface, a rotor that is inserted and fixed to a drive shaft, and is provided with a plurality of vanes that are in sliding contact with the cam surface and disposed inside the cam ring; A vane pump having a drive shaft inserted therein and a pair of side plates disposed on both sides of the cam ring and the rotor and sandwiching both sides of the cam ring and the rotor. The side plate facing the rotor side surface is provided with a vane guide protruding from the plate surface, A groove for supplying back pressure oil of a pump is provided on a surface of the side plate that faces the rotor side surface, and one of the side surfaces sandwiched between the pair of side plates of the rotor faces the one side plate. An annular groove in which the vane guide is accommodated is formed on the side surface, and a lower side opening of the vane groove for mounting the vane communicating with the groove hole and oil are formed on the side surface facing the other side plate. A reservoir recess is formed,A slot for supplying back pressure oil of the pump is a pair of arc-shaped slots formed at point-symmetrical positions with respect to the center point of the side plate, and the slot passes through the front and back of the side plate. It consists of a through-groove hole portion and an enlarged portion formed by a chamfered portion of the through-groove hole portion. Communicating with the recess,The oil sump recess of the rotor is formed into a shape having a wide portion located at a radially outer portion of the rotor and a narrow portion located at the radially inner portion, and the narrow portion Is communicated with the through-groove hole portion and the enlarged-hole portion of the groove hole.
[0012]
According to the first aspect of the present invention, in the vane pump, a vane guide protruding from the plate surface is provided on a surface of the one side plate facing the rotor side surface of the pair of side plates, and the other side plate. The surface of the rotor facing the side surface of the rotor is provided with a slot for supplying back pressure oil of the pump, and the side surface of the rotor that faces the one side plate among the side surfaces sandwiched between the pair of side plates. Is formed with an annular groove in which the vane guide is accommodated, and on the side facing the other side plate, the lower side opening of the vane groove for attaching the vane communicating with the groove hole and for oil sump Since the recess of is formed,
On one side of the rotor, the contact area with the one side cover is reduced by reducing the facing area due to the presence of the vane guide and the presence of the annular groove therefor, and on the other side of the rotor, The back pressure oil of the pump is supplied into the oil reservoir recess through the slot, and the oil filled in the recess is effectively introduced and supplied to the gap between the rotor side surface and the other side plate. A continuous oil film is formed in the gap, smooth rotation of the rotor is promoted, frictional heat generation due to sliding contact is suppressed, pump damage due to seizure is reliably prevented, and pump operating efficiency is improved. Is done.
Further, since side plates with vane guides provided on both side surfaces of the rotor are not disposed, the pump unit can be prevented from being enlarged, and it is not necessary to provide vane guide grooves on both side surfaces of the rotor. Therefore, the strength of the rotor is maintained without any loss, and the safety of the pump operation is ensured.
[0013]
  In the invention of claim 1,A slot for supplying back pressure oil of the pump is a pair of arc-shaped slots formed at point-symmetrical positions with respect to the center point of the side plate, and the slot passes through the front and back of the side plate. It consists of a through-groove hole portion and an enlarged portion formed by a chamfered portion of the through-groove hole portion, both of the through-groove hole portion and the enlarged hole portion being used for the lower opening of the vane groove of the rotor and the oil reservoir. Since it communicates with the recess, efficient back pressure oil is supplied from the arc-shaped groove and the enlarged hole to the lower opening of the vane groove and the recess for oil sump, and is supplied to the lower opening of the vane groove. The vane is pushed upward from below by the back pressure oil, and the upper part thereof is reliably brought into contact with the cam surface of the cam ring inner peripheral surface. In addition, since the back pressure oil supplied to the oil reservoir recess is supplied from the through groove hole portion and the enlarged hole portion of the groove hole, the oil is efficiently supplied to the gap between the rotor side surface and the side plate and lubricated. The effect is improved, and the occurrence of seizure in the gap is almost completely prevented.
[0014]
  In the invention according to claim 1, the oil sump recess of the rotor has a shape including a wide portion positioned at a radially outer portion of the rotor and a narrow portion positioned at the radially inner portion. Since the narrow portion communicates with the through-groove hole portion and the enlarged hole portion of the groove hole, the shape effect in the radial direction of the oil reservoir recess and the oil reservoir via the enlarged hole portion are formed. Combined with the reliable oil supply to the narrow recess, the oil supply in the radial direction of the rotor and side plate is reliably and equalized, and a uniform oil film is formed over the entire area in the gap between the two. The lubrication effect is improved.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described below with reference to FIGS.
First, an outline of the structure of the vane pump P in the present embodiment will be described with reference to FIGS.
[0016]
The vane pump P is sandwiched by a pump unit U, a housing H composed of a body 1 as a first housing part and a cover 2 as a second housing part, and the body 1 and the cover 2, and a plurality of bolts B 1 and a cover 2 which is integrally coupled with the cover 2. The cover 2 is formed with a recess 2 b that opens at a mating surface 2 a with the seal plate 3, and the recess 2 b is covered with the seal plate 3, thereby forming a storage chamber 4 in which the pump unit U is stored.
[0017]
The drive shaft 5 of the vane pump P that is rotationally driven by the power of the internal combustion engine (not shown) is on the base end side where the power transmission member mounting portion 5a for transmitting the power of the crankshaft of the internal combustion engine is provided. It is rotatably supported by the housing H via a fixed slide bearing 6 and a slide bearing 7 fixed to the bottom wall 2c forming the storage chamber 4 on the tip end side.
[0018]
The pump unit U includes an annular cam ring 10 having an outer peripheral surface 11 formed of a cylindrical surface and an inner peripheral surface 12 having an approximate shape of an ellipse, a rotor 20 disposed inside the cam ring 10, and a circumferential direction of the rotor 20. A plurality of vanes 21 slidably inserted in a plurality of vane grooves 22 provided in the radial direction at equal intervals and a side surface of the cam ring 10 and the rotor 20 on the body 1 side. A first side plate 30 to cover and a second side plate 40 to cover the side surface of the cam ring 10 and the rotor 20 on the cover 2 side are provided.
[0019]
The pair of through holes 13 provided in the cam ring 10 so as to face each other in the diameter direction pass through in the rotation axis direction A1, and the pair of press-fit holes 31 and the second side plate 40 provided in the first side plate 30. In the state in which the rotor 20 is disposed inside the cam ring 10 and the cam ring 10 is sandwiched between the first and second side plates 30, 40. 10 and a pair of positioning pins 8 that align the positions of the side plates 30 and 40 in the circumferential direction.
[0020]
The pump unit U configured by integrating the cam ring 10, the rotor 20, the vane 21, and both side plates 30 and 40 with both positioning pins 8 is inserted into the drive shaft 5 held in the body 1, The projecting portions 8a and 8a of the positioning pins 8 and 8 from the first side plate 30 are press-fitted into the pair of press-fitting holes 3a of the seal plate 3 and the pair of press-fitting holes 1a of the body 1, respectively. Fixed. Thereafter, the cover 2 is put on the body 1 and fastened by the bolt B so that the second side plate 40 and the cover 2 are oil-tight by the O-ring 9.
[0021]
A mounting hole 20b having a spline 20a formed on the peripheral wall surface is formed at the center of the rotor 20, and the spline 5b provided on the outer peripheral surface of the drive shaft 5 inserted into the mounting hole 20b is fitted to the spline 20a. Thus, the drive shaft 5 and the rotor 20 are coupled and fixed so as to be integrally rotatable.
[0022]
The tip of each vane 21 is in sliding contact with the cam surface 12a formed on the inner peripheral surface 12 of the cam ring 10, and is between the cam surface 12a and the outer peripheral surface of the rotor 20, and the first and second The spaces between the side plates 30 and 40 are partitioned by the plurality of vanes 21, so that a plurality of pump chambers 50 (see FIG. 1) composed of variable volume chambers whose volumes change according to the rotation of the rotor 20. It is formed.
[0023]
A part of the hydraulic oil discharged from each pump chamber 50 passes through an arc-shaped groove 42 formed in the second side plate 40 described later (see FIG. 5), and the side opening 22a of each vane groove 22 is provided. After that, the groove at the bottom of the groove 22 is supplied to the back pressure chamber 22c at the bottom of the vane groove 22 (see FIG. 6). Therefore, during the operation of the vane pump P, each vane 21 is pushed radially outward in the vane groove 22 by this back pressure oil, and the tip of each vane 21 is pushed to the inner peripheral surface 12 of the cam ring 10. It is pressed against the formed cam surface 12a.
[0024]
The cam ring 10 has a pair of first and second suction ports and a pair of first and second discharge ports that communicate with the pump chamber 50 in a predetermined range in the circumferential direction at a position facing the cam ring 10. A port is formed. However, the suction port and the discharge port are not clearly illustrated, and the discharge port 14 which is a part of the suction port and the discharge port is only illustrated in FIG.
[0025]
The hydraulic fluid sucked from the suction port is pressurized in a pump chamber 50 which is a variable volume chamber partitioned by a plurality of vanes 21 moving forward and backward on the outer peripheral surface of the rotor 20 and both side plates 30 and 40, and clearly Is discharged through the discharge port 14 (not shown) or the like (see FIG. 1), supplied via a predetermined oil passage, control valve, etc. (not shown) for shift control in the CVT which is a continuously variable transmission. Is supplied to the back pressure chamber 22c in the lower portion of the vane groove 22 through the arc-shaped groove 42 of the second side plate 40, which will be described later, as described above, and also to the oil reservoir recess 24, which will be described later, on the side surface 20B of the rotor. Is also supplied (see FIG. 6).
[0026]
The outline of the structure of the vane pump in the present embodiment is as described above.
Incidentally, the rotor 20 is covered with the pair of first and second side plates 30 and 40 together with the cam ring 10 as described above, as well as the cam ring 10 as shown in FIG. More specifically, in the state where the rotor 20 is sandwiched between the side plates 30 and 40, more specifically, both side surfaces 20A and 20B are covered with both side plates 30 and 40 with a very slight gap. Drive rotation for operation is performed.
[0027]
Of the pair of side plates 30 and 40 that cover the rotor 20 so as to sandwich the first side plate 30, the first side plate 30 is a plate-like body having a predetermined thickness, as shown in FIGS. The surface of the plate-like surface that does not oppose the rotor side surface 20A does not have any particular structural feature. However, the surface facing the side surface 20A of the rotor 20 has a function of moving the vane 21 up and down by the rotation of the rotor 20. A vane guide 32 serving as a guide is provided. Note that 33 is a communication port for hydraulic oil, and 31 is a press-fitting hole for the positioning pin 8.
[0028]
As shown in FIGS. 3A and 3B and FIGS. 4A and 4B, the vane guide 32 has an elliptical outer contour similar to the cam surface 12a of the inner peripheral surface 12 of the cam ring 10 described above. Are formed in a ring shape having an outer peripheral portion 32a and a perfect circular inner peripheral portion 32b. Therefore, the ring has a wide ring width in the long side direction 32c as a whole, This is a deformed ring in which the ring width is narrow in the short side direction 32d orthogonal to the long side direction.
[0029]
The ring forming the vane guide 32 has a predetermined uniform thickness, and the surface 32e is flat. For example, a metal plate such as a steel plate is punched out by press machining and appropriately subjected to heat treatment or the like. The hardness of the cam ring 10 is similar to that of the cam surface 12a of the cam ring 10, that is, the outer peripheral portion 32a, that is, the sliding contact portion with the lower portion 21a of the vane 21 is subjected to barrel finishing or the like. Has been.
[0030]
As shown in FIGS. 3A and 3B, the vane guide 32 is arranged so that its elliptical ring center O2 coincides with the center 01 of the first side plate 30, and in the cam ring. The ring formed on the surface of the plate 30 in a state in which the positional relationship between the circumferential surface 12 and the cam surface 12a is taken into consideration and the thickness direction of the ring protrudes from the surface of the plate 30. Is fixed to the plate 30 by being fixed by a fixing means such as caulking by a fixing pin 32f, and fixed for the mounting by the pin 32f. In the long side direction 32c of the elliptical ring, two wide symmetrical positions 32g and 32g sandwiching the center of the ring are made.
[0031]
The vane guide 32 attached to the first side plate 30 has a ring portion protruding in the ring thickness direction of the vane guide 32 after the pump unit U is assembled in an annular groove 23 on the side surface 20A of the rotor 20 described later. As shown in FIG. 7, the vane guide 32 advances and retracts on the outer peripheral surface 32a of the rotor 20 when the outer peripheral portion 32a rotates in the annular groove 23. The vane 21 is in sliding contact with the lower portion 21a of the moving vane 21, and functions to smoothly move up and down in the rotor 20 of the vane 21 (see also FIG. 1).
[0032]
As shown in FIGS. 5A and 5B, the second side plate 40 is a plate-like body having a predetermined thickness, and the plate-like surface penetrates both the front and back surfaces of the plate 40. A position on the same circumference that is point-symmetric with respect to the center O3 of the plate 40, that is, a lower side opening 22b of a side portion of a vane groove 22 formed in a side surface 20B of the rotor and a recess for oil sump A pair of arc-shaped groove holes 42 having a predetermined length are formed at corresponding positions (see FIG. 6) that communicate with the opening in the lower part, and the groove holes 42 have the predetermined lengths in the respective circumferential directions. Is set. Reference numeral 41 denotes a fitting groove for the positioning pin 8.
[0033]
The length of each arcuate slot 42 is such that the arcuate opening formed by the slot 42 is substantially equal to two or three of the lower side openings 22b of the vane groove 22 in the rotor 20 and lubrication described later. The width of the slot 42 is relatively narrow, and the length of the slot 42 is relatively narrow, and the width of the slot 42 is relatively small. The groove hole 42 includes a through groove hole part 42a that penetrates the plate 40 and an enlarged hole part 42b in which an inner circular arc part of the through groove hole part 42a is chamfered (see FIG. 9). .
[0034]
And the through-groove hole part 42a of each circular arc-shaped groove hole 42 and the enlarged hole part 42b which is a chamfering part of this through-groove hole part 42a are the said vane groove | channel 22 in the rotor 20, as shown in FIG. The lower opening 22b of the vane groove 22 communicates with the lower back pressure chamber 22c of the vane groove 22 and simultaneously communicates with the narrow portion 24b of the oil sump recess 24 in the rotor 20, The oil is reliably supplied to the recess 24.
[0035]
Due to the above structure, each arc-shaped groove 42 has two or three vanes via the lower side openings 22b of the two or three vane grooves 22 of the rotor 20 during the pump operation as described above. A part of the back pressure oil discharged from the pump chamber 50 can be simultaneously introduced into the back pressure chamber 22c at the bottom of the groove 22, and the back pressure oil can be introduced into the back pressure chamber 22c at the lower portion of the vane groove 22. Two or three vanes 21 are simultaneously pushed up from below, and the upper portion of the vanes 21 is constantly pressed against the cam surface 12a of the inner peripheral surface 12 of the cam ring 10.
[0036]
Further, a part of the back pressure oil introduced from the arc-shaped groove hole 42 is formed on the side surface 20B of the rotor 20 through the groove hole 42 and an enlarged portion 42b which is a chamfered portion of the groove hole. The oil is supplied to two or three oil reservoir recesses 24 at the same time, and the oil supplied to these oil reservoir recesses 24 contributes to friction prevention by sliding contact between the side surface 20B of the rotor 20 and the second side plate 40. To do.
[0037]
The rotor 20 sandwiched and covered by the first and second side plates 30 and 40 is shown in FIGS. 6A, 6B, and 6C, and a part of the structure is as described above. An attachment hole 20b provided for attachment to the drive shaft 5 (see FIG. 2) is provided in the central portion of the cylinder to form a ring-like cylinder, and radially in the circumferential direction of the outer peripheral surface of the cylinder at equal intervals. Grooves 22 are provided so as to be provided to a plurality of vanes 21 that are directed to reach a substantially central portion of the wall thickness in the radial direction of the ring-shaped cylinder and pass through between both side surfaces of the ring-shaped cylinder. ing.
[0038]
And the rotor 20 which makes this ring-shaped cylindrical shape equips one side 20A which the 1st side plate 30 opposes with the cyclic | annular groove | channel 23 which goes around the substantially center part in radial direction thickness of this side 20A. The annular groove 23 is formed as a groove 23 that circulates on the same radius of the predetermined width on the side surface 20A.
[0039]
Therefore, the annular groove 23 is a circular groove having a predetermined width, and the groove 23 is an ellipse similar to the cam surface 12a of the cam ring inner peripheral portion 12 provided to protrude from the surface of the first side plate 30. The circular groove 23 is provided for the accommodation of the vane guide 32, and the circular annular groove 23 is for the purpose of accommodation in consideration of the relative rotation with the elliptical vane guide 32. And a predetermined depth in consideration of the amount of protrusion of the vane guide 32.
[0040]
By the way, the annular groove 23 is a groove formed so as to circulate along the side surface 20A with a predetermined width at a substantially central portion in the radial thickness of the side surface 20A of the rotor 20. The side lower half of the vane groove 22 provided for the vane 21 (which corresponds to the lower side opening 22b of the vane groove 22) competes with the side surface 20A. Therefore, for this purpose, the annular groove 23 is formed by cutting off the lower half of the vane groove 22 substantially.
[0041]
The annular groove 23 has a lower side opening 22b at the bottom 23a, which is an opening extending from a position near the center of the side opening 22a of the vaned groove 22 of the rotor 20 to a low position. In a substantially shared state, the outer peripheral portion 32a of the vane guide 32 of the first side plate 30 accommodated in the annular groove 23 after the assembly of the pump unit U is arranged so that the vane 21 in the vane groove 22 It is made to contact | abut directly on the lower part 21a (refer FIG. 7). This structure stabilizes and smoothly moves the vane 21 up and down during the rotation of the rotor 20.
[0042]
A plurality of relatively shallow recesses 24 are formed on the other side surface 20B of the rotor 20 facing the second side plate 40, as shown in FIGS. 6B and 6C. 24 is provided as an oil sump for lubrication, and its shape is directed outward in the radial direction of the rotor 20 so that its upper part is a wide part 24a and its lower part is a narrow part 24b. It has a shape similar to that of a brush, and is formed on the side surface 20B of the rotor 20 with radial vanes 22 at just equal intervals in the radial direction.
[0043]
Then, after assembling the pump unit U, as shown in FIG. 8, the circles of the second side plate 40 described above are simultaneously applied to the narrow portions 24b of the two or three concave portions 24 having a mold similar to this polishing. The through-groove hole portion 42a and the shallow lower expanded-hole portion 42b of the arc-shaped groove hole 42 face each other and communicate with each other. Therefore, the pump chamber 50 introduced through the arc-shaped groove hole 42 as described above. A part of the back pressure oil from the oil flows into the two or three recesses 24 through the through-groove hole portion 42a and the enlarged hole portion 42b at the same time. The oil is stably supplied to a slight gap between the side surface 20B of the rotor 20 and the second side plate 40, and a continuous oil film for lubrication is formed in the gap.
[0044]
The rotor 20 and the first and second side plates 30 and 40 each have the above-described structure. As described above, the rotor 20 having the vane 21 mounted inside the cam ring 10 is accommodated, and the first By sandwiching both side surfaces of the cam ring 10 by the first and second side plates 30 and 40, the rotor 20 is covered with the side plates 20 and 20B by the side plates 30 and 40, and these side plates 30 and 40 serve as the rotor. The above-described pump unit U is constructed by being arranged facing each other on both side surfaces 20A and 20B.
[0045]
Then, due to the face-to-face arrangement of the first side plate 30 on the rotor side face 20A after assembling the pump unit U, the side face 20A facing the first side plate 30 of the rotor 20 is as shown in FIG. A portion of the ring-shaped vane guide 32 provided with the elliptical outer peripheral portion 32 a of the first side plate 30 is accommodated in the annular groove 23 of the rotor 20.
[0046]
The vane guide 32 has its outer peripheral portion 32a abuts and supports the lower portion 21a of the vane 21 from the lower side in the retracted state. Therefore, when the rotor 20 rotates, the lower portion 21a of the vane 21 is slidably guided in a synchronous relationship with the cam surface 12a of the cam ring inner peripheral surface 12 along the elliptical shape of the outer peripheral portion 32a of the vane guide 32. 21 is moved up and down along the vane groove 22.
[0047]
Further, the side surface 20B facing the second side plate 40 of the rotor 20 is shown in FIGS. 8 and 9 due to the face-to-face arrangement of the second side plate 40 on the rotor side surface 20B after the pump unit U is assembled. As described above, the pair of arc-shaped groove holes 42 of the second side plate 40 are connected to each other via two or three lower side openings 22b of the vane grooves 22 that open to the side surface 20B of the rotor at the point-symmetric positions. Simultaneously communicating with two or three bottom back pressure chambers 22c of the groove 22 and simultaneously communicating with two or three oil reservoir recesses 24 formed on the rotor side surface 20B.
[0048]
Therefore, part of the oil discharged from the pump chamber 50 (see FIG. 1) in the operation of the vane pump P passes through the pair of arcuate grooves 42 and the bottom back pressure chamber 22c of the vane grooves 22 at a plurality of point symmetrical positions and the oil. It is simultaneously introduced and supplied to the reservoir recess 24 in a well-balanced manner. Simultaneously with the supply, an enlarged hole portion 42b formed as a chamfered portion in the arc-shaped groove 42 is simultaneously communicated with a plurality of narrow portions 24b of the oil sump recess 24 at point-symmetrical positions. The oil is supplied from the hole 42b to the recess 24 simultaneously with the supply (see FIG. 9).
[0049]
Then, by supplying oil to the bottom back pressure chamber 22c of the vane groove 22, the lower portion 21a of the vane 21 is pushed up as described above, and the upper portion of the vane 21 is formed on the cam surface 12a of the inner peripheral surface 12 of the cam ring 10. In addition, by supplying oil to the oil sump recess 24, oil for lubrication is efficiently and reliably supplied to the gap between the rotor side surface 20B and the second side plate 40 as described above. The
[0050]
Since the embodiment shown in FIGS. 1 to 9 of the present invention has the above-described configuration, the rotor 20 sandwiched and covered by the first side plate 30 and the second side plate 40 has one side surface 20A. By the first side plate 30 provided with the vane guide 32, the other side surface 20B has an arc shape that can supply a part of the back pressure oil of the pump discharge oil to the oil sump recess 24 formed on the side surface 20B. Since the second side plates 40 having the groove holes 42 are sandwiched and covered, the occurrence of seizure due to the sliding contact between the rotor 20 and the side plates 30 and 40 is effectively prevented. .
[0051]
Since a plurality of oil sump recesses 24 are formed on the side surface 20B of the rotor facing the second side plate 40, the oil retained and retained in the oil sump recesses 24 causes a gap between the rotor 20 and the side plate 40. Since a continuous strong oil film is formed in a slight gap between the rotor 20 and the side plate 40, smooth relative rotation between the rotor 20 and the side plate 40 is promoted, and the rotor 20 and the side plate 40 are not seized. The damage of P is effectively prevented, the safe and smooth operation of the pump P is ensured, and the operation efficiency is improved.
[0052]
The oil is supplied to the oil sump recess 24 formed on the rotor side surface 20B by supplying a through groove hole 42a of the arcuate groove hole 42 formed at a pair of point-symmetric positions in the second side plate 40 and its chamfering. In addition, the oil is supplied to the plurality of oil retaining recesses 24 in a point-symmetrical position in a well-balanced manner, so that the oil is supplied to the oil sump recesses 24. This is ensured, and the oil is uniformly and efficiently supplied over the entire area of the slight gap between the rotor side surface 20B and the second side plate 40, and the lubrication efficiency is enhanced.
[0053]
The oil sump recess 24 formed on the rotor side surface 20B has a shape that widens outwardly in the radial direction of the rotor 20, and therefore depends on its shape characteristics and the enlarged portion 42 b of the arcuate groove 42. Combined with the reliable oil supply to the narrow portion 24b in the radially inward direction of the oil sump recess 24, it can be made uniform in a slight gap between the side surface 20B of the rotor 20 and the second side plate 40. Oil can be reliably supplied.
[0054]
Since the oil sump recess 24 is formed on the side surface 20B of the rotor 20, the side plate 40 facing the rotor side surface 20B on which the oil sump recess 24 is formed does not have the vane guide 32 and the rotor side surface 20B. Since the above-described seizure can be prevented, the pump unit U can be prevented from being enlarged. Further, it is not necessary to form annular grooves 23 for vane guides on both side surfaces 20A and 20B of the rotor 20, and seizure of the rotor 20 and both side plates 30 and 40 can be achieved without impairing the strength of the rotor 20. It can be almost completely eliminated.
[0055]
The vane 21 that moves forward and backward in the outer peripheral portion of the rotor 20 is slidably guided by the outer peripheral portion 32a of the vane guide 32 provided in the first side plate 30 at the lower portion 21a, and the vane 21 maintains a stable state. Then it moves up and down.
[0056]
Further, the sliding contact guide in the raising / lowering operation of the vane 21 by the vane guide 32 is coupled with the substantial reduction of the facing area by the annular groove 23 provided for the vane guide 32 on the rotor side surface 20A. The effect of alleviating and softening the sliding contact between the first side plate 30 and the side surface 20A of the rotor 20 is achieved, and the occurrence of seizure due to friction between the plate 30 and the side surface 20A of the rotor 20 is almost completely eliminated. .
[0057]
Other embodiments are possible instead of embodiments of the present invention.
[0058]
In the embodiment of the present invention, the arcuate slot 42 formed in the second side plate 40 is a pair formed at a point-symmetrical position, but is not limited thereto. For example, it may be a plurality of grooves formed as appropriate by extending at equal intervals on the same circumference of the plate 40. Further, the length and width of the slot are also appropriately selected.
[0059]
In the embodiment of the present invention, the oil sump recess 24 formed on the rotor side surface 20B has a shape substantially similar to that of the final polishing, but the shape of the recess 24 does not depart from the spirit of the present invention. It can be selected and adopted as appropriate within the range.
[Brief description of the drawings]
FIG. 1 is an external view of a vane pump according to the present invention, with a part thereof broken away.
FIG. 2 is a view showing a main structural part of the vane pump of the present invention, and is a cross-sectional view taken along line AA in FIG.
FIG. 3 is a view showing one side plate of the vane pump of the present invention, (a) is a view showing a surface structure of the plate facing one side of a rotor, and (b) is a view (a). FIG.
4A and 4B are views showing the structure of the vane guide of the present invention, in which FIG. 4A is a plan view, and FIG.
5A is a view showing the other side plate of the vane pump of the present invention, FIG. 5A is a view showing the surface structure of the plate facing the other side surface of the rotor, and FIG. It is DD sectional drawing in).
6A and 6B are views showing the structure of the rotor of the vane pump of the present invention, where FIG. 6A is a view seen from the direction of arrow A in FIG. 6B, and FIG. (C) is the figure seen from the arrow B direction in (b).
FIG. 7 is an explanatory diagram showing a facing relationship between one side surface of a rotor and one side plate according to the present invention.
FIG. 8 is an explanatory diagram showing a facing relationship between the other side surface of the rotor and the other side plate in the present invention.
FIG. 9 is a diagram for explaining the facing relationship between the other side surface of the rotor and the other side plate according to the present invention, and is a cross section taken along line FF in FIG.
FIG. 10 is a cross-sectional view showing the main structure of a conventional vane pump.
11 is a view showing a main structural part of a conventional vane pump, and is a cross-sectional view taken along the line 0A-0A in FIG. 7;
FIG. 12 is an exploded perspective view of a main structure portion in a conventional vane pump.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Body, 2 ... Cover, 3 ... Seal plate, 4 ... Storage chamber, 5 ... Drive shaft, 6, 7 ... Sliding bearing, 8 ... Positioning pin, 9 ... O-ring, 10 ... cam ring, 11 ... cam ring outer peripheral surface, 12 ... cam ring inner peripheral surface, 12a ... cam surface, 13 ... through hole, 14 ... discharge port, 20 ... rotor, 20a ... spline, 20b ... mounting hole, 20A, 20B ... side surface of rotor, 21 ... vane, 21a ... lower part of vane, 22 ... vane groove, 22a ... Vane groove side opening, 22b ... Lower side opening, 22c ... Back pressure chamber at the bottom of the vane groove, 23 ... Annular groove, 23a ... Lower, 24 ... Oil sump Concave portion for use, 24a, wide portion, 24b, narrow portion, 30 ... first side plate, 30a, groove-shaped portion, DESCRIPTION OF SYMBOLS 1 ... Press-fit hole, 32 ... Vane guide, 32a ... Outer peripheral part, 32b ... Inner peripheral part, 32c ... Long side direction, 32d ... Short side direction, 32e ... Surface Exposed portion, 32f ... fixing pin, 32g ... wide symmetrical position, 40 ... second side plate, 41 ... insertion groove, 42 ... arc-shaped groove hole, 42a ... through Groove hole part 42b ... enlarged hole part 50 ... pump chamber, P ... vane pump, U ... pump unit, H ... housing, A1 ... rotational axis direction.

Claims (1)

A cam ring having a cam surface on an inner peripheral surface, a rotor that is inserted and fixed to the drive shaft, and that is provided with a plurality of vanes that are in sliding contact with the cam surface and is disposed inside the cam ring; and In the vane pump provided with a pair of side plates that are inserted and disposed on both sides of the cam ring and the rotor and sandwich the cam ring and both sides of the rotor.
Of the pair of side plates, a vane guide protruding from the plate surface is provided on a surface of the one side plate facing the rotor side surface, and a surface of the other side plate facing the rotor side surface is provided with a pump. Slots for supplying back pressure oil are provided,
An annular groove in which the vane guide is accommodated is formed on a side surface facing the one side plate among both side surfaces sandwiched between the pair of side plates of the rotor, and faces the other side plate. On the side surface, a lower side opening of the vane groove for mounting the vane communicating with the groove hole and a recess for oil sump are formed,
A slot for supplying back pressure oil of the pump is a pair of arc-shaped slots formed at point-symmetrical positions with respect to the center point of the side plate, and the slot passes through the front and back of the side plate. It consists of a through-groove hole portion and an enlarged portion formed by a chamfered portion of the through-groove hole portion. Communicating with the recess,
The oil sump recess of the rotor is formed into a shape having a wide portion located at a radially outer portion of the rotor and a narrow portion located at the radially inner portion, and the narrow portion Is a vane pump characterized in that it communicates with the through-groove hole portion and the enlarged hole portion of the groove hole.

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